【摘要】 提出一种在矢量地图中嵌入水印的算法,对地图按坐标平均分块,根据每块顶点密度的分类对水印的强度进行自适应调制,然后在地图的精度允许范围内,采用改变顶点坐标值的方法将二值水印图像重复嵌入到地图中,并且通过双门限联合检测提取水印.该算法能够在保证地图的精度的同时,有效地增强水印的强度.实验证明该算法具有良好的鲁棒性.更多还原

【Abstract】 An algorithm for watermarking of the vector map is presented. we lay a rectangular grid over the map; according to the classification of density of vertices in each block we modulate the intensity of watermark adaptively, in the tolerance of the coordinates, and a two-value watermark image is embedded repeatedly by displacing the coordinates of vertices. When extracting the watermarks double-threshold combinative detection is used, the proposed algorithm can enhance the intensity of watermarks and ensure the precision and usability of the map. Experimental results show that this algorithm is robust to some processing.更多还原